OST-034: Noir Crowning

[oldeskewltoy]

I got a request........




More to come....

[pack]

Oh man.... sweet..!

[Bean]

Is it just me or does the 16V benefit more from porting than 20V regarding flow benefits?

[oldeskewltoy]

(08-06-2015 06:19 PM)Bean Bandit Wrote:  Is it just me or does the 16V benefit more from porting than 20V regarding flow benefits?

lets see.......




the intake side.....


paper towel in exhaust port is acting as a "cork", remember these are used valves, in used seats, and stuffing the opposite port to the one being test allows for honest figures.




The numbers @ 28".......


Unported Intake -

• .050 - 58.15
• .100 - 110.87
• .150 - 146.30
• .200 - 168.30
• .250 - 180.08
• .300 - 186.65
• .350 - 191.22
• .400 - 194.10
  

Ported Intake -

• .050 - 60.02
• .100 - 114.30
• .150 - 149.20
• .200 - 177.33
• .250 - 185.47
• .300 - 192.33
• .350 - 197.78
• .400 - 202.35
  

There is a glaring error on one reading, can anyone find it??? I likely over adjusted one valve, What should it read (about/approximate)??


setting up to do the exhaust side




Unported Exhaust -

• .050 - 32.45
• .100 - 65.52
• .150 - 90.95
• .200 - 110.12
• .250 - 122.80
• .300 - 130.25
• .350 - 135.48
• .400 - 140.43
  

Ported Exhaust -

• .050 - 35.38
• .100 - 65.88
• .150 - 93.73
• .200 - 113.50
• .250 - 130.63
• .300 - 139.92
• .350 - 146.33
• .400 - 151.20
  

More to come......

[oldeskewltoy]

Nearly a 2 week delay...

I had a talk with my client, he is hoping for an exhaust to intake flow ratio approaching 80%. This is going to be extraordinarily difficult because the stock Blacktop flows about 61%, and the first attempt at porting the exhaust side did improve things, now 67%, but a further gain of 13% seems a long goal at best.

My first attempt at porting the exhaust was limited because I didn't have a gasket to know where my edges were, and I didn't want to port beyond the gasket, for doing that would cause serious flow issues. So the initial porting on #4 exhaust was from about 33.6 to about 33.7, because not knowing the exhaust gasket left me a bit in the dark.

My client sent me the OEM gasket



Port on far right is #4, even with the gasket in the "down" position, there is still some room available in the port roof, and room all the way around the port.

So now that I had a gasket, work begins on #2 exhaust port. Redline is the gaskets edge.






A bit more dramatic....





The stock Blacktop gasket outlet is 36mm. Port #2 is now out to 34.8mm





Later this week I'll get this on the bench and see what if any improvement there is over the first numbers.


More to come........

[banpei]

That's a lot of area you gained!

[oldeskewltoy]

oldeskewltoy Wrote:

Later this week I'll get this on the bench and see what if any improvement there is over the first numbers.

The numbers @ 28".......

Ported Exhaust (#4 - port on left) -

• .050 - 35.38
• .100 - 65.88
• .150 - 93.73
• .200 - 113.50
• .250 - 130.63
• .300 - 139.92
• .350 - 146.33

More to come......

"New" exhaust port readings, #2 port - on right

• .050 - 34.98
• .100 - 65.03
• .150 - 93.67
• .200 - 113.32
• .250 - 131.88
• .300 - 142.53
• .350 - 150.92

The reason testing stopped @ .350 was my client is limited to 9mm of lift (.354")



So now the intake @ .350" is @ 197.8cfm, while the exhaust is now @ 150.9, the exhaust to intake flow ratio is now a tick over 75% at peak lift, and over the lift range the exhaust to intake ratio is now about 71.5% (was 61%)


More to come.....

[oldeskewltoy]

a few views of working the exhaust side.....


minimizing the guide boss, and tapering the guide - both to minimize their effect on the outgoing exhaust flow



reshaping the exhaust port - maximizing flow



3 ports down.... one to go




more to come.....

[oldeskewltoy]

[oldeskewltoy]

Now to finish up the intakes and the chambers....


More to come.......